Apparatus to selectively remove powder from coated sheet material



June 2, 1970 E. 1'. TURNEY, JR

APPARATUS TO SELECTIVELY REMOVE POWDER FROM COATED SHEET MATERIAL 3Sheets-Sheet 1 Filed June 5, 1967 INVENTOR. EUGENE T TUR/UEY c/R.

E. T. TURNEY, JR APPARATUS 1'0 SELECTIVELY REMOVE POWDER June 2, 1970FROM COATED SHEET MATERIAL 3 Sheets-Sheet 2 Filed June 5. 1967 INVENTOR.EUGEIUE 7T TUR/UEY JA IQTTORNE).

June 2, 1970 E. T. TURNEY, JR 3,514,803

APPARATUS T0 SELECTIVELY REMOVE POWDER FROM COATED SHEET MATERIAL FiledJune 5, 1967 3 Sheets-Sheet 3 INVENTOR. I 13%, E UGE IUE 7T TUR/UEY JR.

QTTOR/UE).

United States Patent 3,514,803 APPARATUS TO SELECTIVELY REMOVE POWDERFROM COATED SHEET MATERIAL Eugene T. Turney, Jr., 1112 S. North LakeDrive, Hollywood, Fla. 33021 Filed June 5, 1967, Ser. No. 643,615 Int.Cl. A471 /00 US. Cl. -306 7 Claims ABSTRACT OF THE DISCLOSURE Apparatusfor and process of removing excess powder from the face surfaces ofsheets which have been treated by selectively coating certain face areaswith a material to hold a film of powder thereon; the sheets having alayer of powder thereover are moved in a plane of travel between opposedelongate vacuum nozzles, one of the nozzles providing a vacuum force tolift free powder from the powdered face surfaces of the sheets to removethe excess, and the other and opposed nozzle providing a vacuum force ofbalance on the underside or unpowdered surface of the sheet to resistlifting of the sheet and maintain the sheets in their plane of travel.

This invention pertains to an apparatus for removing excess powder fromcoated and uncoated surface areas of sheets, and, more particularly, toan apparatus to be used in combination with a device which continuouslydeposits a uniform fall of powder on sheets having surface areas coatedwith a material to hold a film of powder on said surface areas.

In the past, various types of thin signs, nameplates, etc. have beenmade by a process which includes selectively coating certain areas. Thestep of coating with powder has been one which presents no majorproblem; however, a problem has been encountered in cleaning the excesspowder from the coated and uncoated areas. In general practice, this isaccomplished by exposing the powdered surfaces to vacuum forces on thepowdered side only, i.e., on one side of the thin coated material,which, of course, necessitated some means for holding the sheet down soas not to be drawn up to pass in scraping engagement against the vacuumnozzle, in which event the powder coated designs would be marred ordestroyed. In the past, the means to hold the sheet down included theprovision of a shaft extending transversely across the mouth of thevacuum nozzle with a rotating series of relatively thin, spaced discshaving knifelike annular edges to contact the powdered surfaces of thesheets to hold them in the proper spaced relation below the vacuumnozzle. This structure has been somewhat objectionable because a seriesof thin, spaced parallel lines results which is often visible across thepowder coated areas particularly when viewed in certain lights and atcertain angles, and, consequently, there has been a distinct designlimitation in the manufacture of the nameplates by this process.

It is, therefore, a principal object of the instant invention to providea structure for producing this type of sign, plaque, nameplate, etc.which eliminates all need for structural contact with the powderedsurface areas thereof, before, during, or after removal of the excesspowder therefrom.

It is a further object of this invention to apply a first vacuum forceof lift to the powdered surfaces of the sheets to remove the excesspowder and which tends to lift the sheet; and a countervailing secondvacuum force to the opposite sheet side or back, which is unpowdered tobalance against the lift force on the sheets so that the p CC same tendto float past the powder removal station without material deviation fromtheir plane of travel.

Yet another object of the instant invention is to provide a transversesupport shaft in the mouth of the countervailing force-causing nozzle,which nozzle exerts a vacuum force on the back or unpowdered side of thesheets, which shaft is provided with relatively thin, spaced discs tocontact the back surface areas of the sheets and support the unpowderedsurface as required. The vacuum forces utilized are such that the sheetspassing between the two vacuum nozzles are maintained in their plane oftravel and may have contact with the discs on their back or unpowderedsides only.

A still further object of this invention is to provide blower unitshaving their intake sides in communication with the vacuum nozzles toprovide vacuum forces thereto.

In accordance with these and other objects which will become apparenthereinafter, the instant invention will now be described with referenceto the accompanying drawings in which:

FIG. 1 is a schematic side view of the apparatus of the instantinvention and illustrating the powder removal station;

FIG. 2 is a schematic end elevation thereof as viewed from a pointbetween the input and output conveyors;

FIG. 3 is an enlarged detailed view of that portion of FIG. 1illustrating the upper and lower elongate vacuum nozzles of the powderremoval station;

FIG. 4 is a transverse vertical sectional view of the powder removalstation taken along the line 44 of FIG. 3 and looking in the directionof the arrows; and

FIG. 5 is a fragmentary perspective view of a decorative design inaccordance with the instant invention after the powder has been appliedand with the excess powder removed from a portion thereof.

Before referring to the drawings in detail, a preliminary reference toFIG. 5 will be helpful. The sheet 14, it will be noted, is coated with auniform layer or fall of powder 12 to the left of the dotted line 11which represents the powder removal station to be discussed hereinafter.The powder adheres to those areas 16 to which an adhesive has beenselectively applied and rides freely on the areas 14 which have not beenselectively coated. The powder is to be removed from the uncoated areas14 in the powder removal station. Referring to the drawings of thepowder removal station, like reference characters designate like orcorresponding parts throughout the different views; the instantinvention includes generally a powder hopper and discharge nozzle 10 fordepositing a uniform fall of powder 12 on the upper face of the sheet 14which has been selectively coated with the adhesive. A conveyor system18 is provided to transport the sheets 14 downstream from a powderapplication station which includes the powder discharge nozzle 10 to thepowder removal station, which includes a pair of opposed elongate vacuumnozzles 20 and 22 which extend transversely of the line of travel of theconveyor 18 on opposite sides of the plane of passage of the sheets 14'.

In more detail, the sheets 14 may have any desired design, name, etc.applied by so coating one face surface thereof with a material to holdthe powder thereto. The sheets are then placed or fed onto an infeedportion 24 of the conveyor with the coated side up and transportedbeneath the powder discharge nozzle 26, disposed transversely of theinfeed conveyor 24. A continuous uniform fall of powder is provided fromthe powder nozzle to the top surfaces of the sheets. A powder supplyhopper 28 is in communication with the nozzle to provide a continuoussupply thereto and a screen 27 is preferably provided below the mouth ofthe nozzle to facilitate distribution of the powder 12.

The sheets continue downstream to pass between the transverse elongatevacuum nozzles 20 and 22 which are positioned between the input conveyorportion 24 and the discharge conveyor portion 29. Elongate nozzle 20 ispositioned above and adjacent the plane of the top surfaces of thesheets 14 and the nozzle 22 is positioned below and adjacent the planeof the bottom surfaces of the sheets to permit the sheets to pass freelytherebetween, FIGS. 1 and 2. Vacuum forces are applied to both nozzlesby means of blowers 30 and 32 in communication with the nozzles 20 and22 through conduits 34 and 36 respectively, the conduits connecting thenozzles to the intakes of the blowers as at 38 and 40. This dischargeconduits 42 and 44 of the blowers are preferably vented to theatmosphere.

The upper or lift vacuum nozzle 20 which removes the excess powder fromthe treated surface having the coated and uncoated areas of the sheetsis in open communication with a powder reclaim chamber 50 by means of aconduit and hood 52 and 53 respectively, connecting with the transversenozzle 20. Conduit 34 communicates between the reclaim chamber and theintake 38 of blower unit 30.

The upper or lift vaccum nozzle 20 is composed of transverse side walls46 and 48, end walls 50 and 51 and a partial floor 54 preferably angledupwardly from and sized to form the vacuum mouth 56. An appropriatepacking 55 is preferably included between the mouth of the hood 53 andthe nozzle walls.

The lower or balancing vacuum nozzle 22 which supplies thecountervailing force together with weight of the sheet is composed oftransverse side walls 60 and 62, end walls 64 and 66 and a generallyinverted V roof 68, FIG. 3. A series of spaced, parallel slots 70 areprovided across the width of the roof to provide for the vacuum forceson the bottom face surfaces of the sheets and for passage of a series ofspaced discs 72 carried by a transverse shaft 74 extending across andthrough the mouth area 76 of the nozzle 22. The peripheries of thediscs, as best illustrated in FIGS. 3 and 4, extend upwardly through theslots 70 to the plane of the bottom surfaces of the sheets 14. Thus,insofar as the sheets are not balanced by the opposing vertical forcesacting thereon, the only contact with the sheets as they pass betweenthe transverse vacuum nozzles is that of the knife-thin edges of thediscs to apply support forces by rolling over the untreated undersidesthereof.

A third transverse elongate vacuum nozzle 80 may be provided to removethe powder from the conveyor belt, FIGS. 1 and 3. It is preferablypositioned on the underside of the infeed portion 24 of the conveyoradjacent the drive roller 82. The vacuum nozzle 80 communicates with areclaim chamber 84 by means of a conduit 86, and a conduit 88 connectsthe reclaim chamber to the intake of a blower unit 90. An exhaustconduit 92 therefrom is exhausted to the atmosphere.

The drive as illustrated schematically in FIGS. 1 and 3 comes from apower source, not shown, to a sprocket 94 on transverse shaft 96. Thedischarge portion 26 of the conveyor system is driven by a chain 98.Referring to FIG. 3, a chain drive 100 from the driven dischargeconveyor drives the roller 82 of the infeed conveyor as well as the discshaft 54 by means of a chain 102. A pair of driven guide rollers 104 and106 may be utilized immediately adjacent the walls 46 and 60 of thevacuum nozzles as illustrated.

It will be apparent to those skilled in the art that the powder removalstation and process disclosed herein is, useful for partially removingfrom the treated surface of sheet material, a coating of a chemical inpowder form from an area of the sheet material, without marring thesurface. For instance, a powder or asphalt base dust may be employed toprotectively coat an inked area, or, also, a chemical may be employedwhich is characterized by an l affinity for metal so as to adherethereto and hold the powder in selectively treated areas.

The process for removing the excess powder from the treated surface ofsheet material includes the steps of transporting the sheet materialthrough the powder removal station in a generally horizontal attitude,the said sheet carrying a layer of powder material which has beendisposed as a fall thereover and, at the powder removal station,simultaneously, applying a sweep means to lift the excess powder fromthe sheet material, totally from one part and just the excess of thecoating from the other part, and, balancing the lift forces caused bythe sweep action by opposing force on the opposite face of the sheetmaterial which, together with the weight of the sheet balances, is atotal countervailing force to that of the lift by the sweep means sothat the sheet material is not marred or sucked into marring engagementwith the apparatus of the station on passage therethrough.

While there is shown and described what at present is considered apreferred embodiment of the instant invention, it will be obvious tothose skilled in the art that various modifications may be made therein'without departing from the true scope of the invention as defined bythe appended claims.

What is claimed is:

1. A powder removal station which comprises:

(A) apparatus for removing excess powder from a treated face of sheetmaterial selectively coated with an adhesive and carrying a uniformlayer of powder on the treated face;

(B) conveyor means including guide portions to transport the sheetmaterial in a plane of passage through the apparatus and maintaining itin a substantially planar attitude; and

(C) the improvement which resides in opposed sweep and balance means atsaid station to act on sheet material transported past said station,simultaneously,

(1) to sweep the excess powder of said layer from the treated face ofthe sheet material, and

(2) to balance the sheet material in passing through the apparatus freeand clear of marring engagement of the treated surface with saidapparatus,

(3) said lift and balance means comprising:

(a) a sweep nozzle means supported in the apparatus transversely of andjust above the plane of passage to apply lift forces to the treatedsurface to lift the excess powder therefrom,

(b) a balance nozzle means to apply a countervailing force to sheetmaterial in the plane of passage at said station, said balance nozzlemeans being supported by the apparatus beneath said sweep nozzle meansand on the other side of the plane of passage, and

(c) blower means to create a vacuum on the sweep nozzle means and thebalance nozzle means such that the vertical forces, in addition to theweight of the sheet material transported past the said station, aresufficient to lift the excess powder from the treated surface and,simultaneously, to hold the treated surface of the sheet out of marringengagement with the nozzle means and apparatus, and

(d) conduit means to connect the blower means and said nozzle means,wherein said balance nozzle means includes support means within theeffective area of said countervailing force of said balance meanssupporting said sheet material at said station above said planarattitude and physically orienting said sheet relative to said sweepingnozzle means when the force components of the weight of the sheetmaterial and the balance nozzle means are greater than the lift forcesof the sweep nozzle means.

2. The powder removal station as set forth in claim 1 wherein a powderreclaim chamber is provided in the conduit means intermediate the blowermeans and the sweep nozzle means to reclaim excess powder lifted fromthe sheet material.

3. The powder removal station as set forth in claim 1 wherein saidsupport means comprises a shaft across the station including a pluralityof spaced discs of common radius defining a support plane across thestation at the plane of passage for the untreated lower surface of thesheet material, said support means being rotatable.

4. The powder removal station as set forth in claim 1 wherein a powderremoval means is provided in the apparatus in close adjacent proximityto the conveyor means to remove excess powder from the conveyor and saidpowder removal means includes conduit means and is in parallel with saidsweep nozzle means.

'5. The powder removal station as set forth in claim 1 wherein a firstblower means is provided for the sweep nozzle means and a second blowermeans is provided for the balance nozzle means.

6. The powder removal station as set forth in claim 3 wherein saidbalance nozzle means includes a roof having a series of spaced slotswith the circumference of said discs extending outwardly of the roof.

7. The powder removal station as set forth in claim 1 which includesmeans to deliver a fall of powdered material in a uniform layer oversheet material on said conveyor means.

References Cited UNITED STATES PATENTS 1,696,171 12/1928 Libsius 118-631,926,306 9/ 1933 Pettersen 15-306 2,292,596 8/1942 Baechtold 118-63 X2,338,499 1/1944 Paris et al 118-312 X ROBERT W. MITCHELL, PrimaryExaminer US. Cl. X.R.

